This invention relates generally to conveyor systems and, more particularly, to a conveyor lubricating and washing apparatus which is operative to provide a lubricating water and soap mixture between the conveyor belt and the conveyor slider pan and which, after normal conveyor operation has ceased, also operates to direct a spray of hot water and soap or detergent at the conveyor belt for cleansing the belt.
Conveyors are commonly used in institutional settings, such as in the kitchen and dining rooms of hospitals and nursing homes, in connection with the preparation, or make-up, of food trays and for returning used or soiled dishware and utensils from the dinning room to a dishwashing area. When used as a tray make-up conveyor, workers may be stationed at work stations along the length of the conveyor to load the trays as they move past on the conveyor belt and thereby make-up trays of food ready for delivery to patients. When the conveyor is used as a soiled dish conveyor, the trays of dishes or the soiled dishes themselves are returned to the conveyor after the meal and placed on the conveyor belt which transports the tray to the dishwashing area.
Such conveyors typically comprise a continuous fabric belt or a continuous slatted plastic belt trained about a motor-driven drive member at one end and a nondriven rotatable member at the other end. For sanitary reasons and to insure that the conveyor is maintained in good operating condition, apparatus is also commonly provided for cleaning food scraps and the like from the conveyor while it is in use to prevent the buildup and collection of food and other foreign matter on the conveyor belt.
Although the belt and drive mechanisms in early conveyors were usually cleaned manually with brushes, air hoses, water hoses and the like, later developments resulted in automatic wash systems which operate continuously during the operation of the conveyor to eliminate, as much as possible, the costly manual cleaning operations theretofore required.
Such conveyors incorporating automatic washing apparatus are currently available from Seco Products, McGraw-Edison Company, Elgin, Illinois, the assignee of the present invention. Typically, a wash tank is provided at one end of the conveyor, and the conveyor is equipped with soap injection and water spray systems which automatically wash the belt when the conveyor is in operation. The water and soap injection system also extends to the tail section of the conveyor and includes nozzle for spraying the underside of the belt with a mixture of water and detergent to lubricate the belt and reduce friction as the belt rides along a bed, or slider pan, underlying the belt, the belt riding on a thin film of water and detergent on the bed. Excess water is collected in an underlying drain pan.
Other conveyor belt wash systems have been shown in the prior art and, in particular, U.S. Pat. No. 2,266,309, issued to Cohen, shows the use of opposed high pressure water discharge sprays against opposite faces of the conveyor belt and pump means which are used to generate the spray pressure. U.S. Pat. No. 2,541,403, issued to Carl, shows a soiled dish conveyor that utilizes a bath wash in combination with powered brushes operating against both faces of the conveyor to clean the belt and a trough located in the support base under the tail section of the belt into which small amounts of water are continuously fed to lubricate the belt as it passes through the trough.
However, these and other conveyor washing systems heretofore used, operate continuously during normal operation of the conveyor to continuously wash the belt. It has been found, however, that excessive amounts of water, particularly hot water, are required to continuously wash the conveyor belt and that continuous washing is not easily necessary. Accordingly, it is desirable to provide a conveyor which is cleansed at the end of its normal operating cycle, but which is continuously lubricated to reduce friction between the belt and the slider pan, or bed, during normal operation.